January 7, 2025 3:59:39 AM
satellite

Sputnik-1 was a beach ball sized satellite that orbited our planet and sent signals for 3 weeks before 3 of its silver-zinc batteries ran out. Since the launch of Sputnik by the Soviet Union in 1957, satellites have been put into orbit by countries around the world. These satellites range from communication satellites, weather, GPS, space exploration, ozone and carbon-dioxide monitoring etc.

The world’s smallest satellite is Kalamsat, a 3.8 cm cube weighing 64 grams equipped with a Geiger Muller counter for measuring the radiation in Space. It was developed by Rifath Sharook of India in 2017.

The world’s largest satellite is the International Space Station, 365 x 240 ft, almost the size of a football field weighing 408,000 kg.

A satellite is a moon, planet or machine that orbits a planet or a star.

TV and telephone signals travel in straight lines. Before satellites, it was difficult to broadcast over longer distances as the signals did not count for the curvature of the earth. Satellites solved this issue as the signal would be shot off to the satellites reciever and then it would broadcast it back on to multiple points
on earth in just seconds.

Satellites that orbit the earth are categorized as Geo-stationary satellites and Polar satellites.

Geo-stationary satellites orbit at the same speed to the rotation of the earth. From the surface it looks as if they are not moving. These satellites are used for GPS, communication and weather prediction over the country it is positioned above.

Polar satellites are used to photograph the earth as it revolves from pole to pole, north to south, capturing one strip at a time. These satellites help in observing changes on the surface of the earth with regards to forest cover, ice caps changing climates etc.

According to media outlet, The Sun, there were over 6,500 satellites orbiting the Earth, as of September, 2021. About 60% of these were non-functional.

According to Statista, US is the leading country with 2,944 satellites operational in orbit, followed by China and Russia with 499 and 169 respectively. The rest of the world accounts for 1,240 satellites, as of Jan, 2022.

The a whole new generation of low orbit satellites being sent to space to work as internet service providers.

Starlink (from SpaceX) has sent over 2,400 satellites (as of 2022), since 2019. These are small satellites with no propulsion system of its own that are Geo-stationary and beam down internet over the north american continent. This method helps in reaching 99% of customers in US without the need for towers or cables.

Starlink has made it public about its plans to send over 40,000 additional satellites to orbit to make internet accessible to every person on Earth. Considering that Starlink is not the only player in the business with others such as OneWeb and Project Kuiper (from Amazon) all gearing up to take over the world, sky above is definitely getting crowded.

Many organisations have already raised concerns on how bright these mega-constellations are and how it affects astronomy and concerns about space debris from defunct satellites. Most low earth orbiting satellites are designed to fall back onto earth once they have served their mission but sometimes it may orbit the earth for several years before it eventually falls back to earth.

A collision may start a chain reaction that may risk the destruction of other satellites and space stations, knocking of communication systems offline and bringing the entire world to a hault.

Here’s are some quotes from Nasa regarding space debris in Earth’s orbit.

“More than 22,000 objects larger than 4 inches (10 cm) are currently tracked by the U.S. Space Surveillance Network. Only about 1,000 of these represent operational spacecraft; the rest are orbital debris. The estimated population of particles between 0.4 inches and 4 inches (1 to 10 cm) in diameter is approximately 500,000. The number of particles smaller than 0.4 inches (1 cm) probably exceeds tens of millions.”

“In low Earth orbit (below 1,250 miles, or 2,000 km), orbital debris circle the Earth at speeds of between 4 and 5 miles per second (7 to 8 km/s). However, the average impact speed of orbital debris with another space object will be approximately 6 miles per second (10 km/s). Consequently, collisions with even a small piece of debris will involve considerable energy.”

“The most important action today is to prevent the unnecessary creation of additional orbital debris. This can be done through prudent vehicle design and operations. Cleaning up the environment remains a technical and economic challenge that is currently being investigated by the United States and other countries.”

Privatization of space has seen both very positive and some concerning negatives over the past few years.

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